I'm not a fan of a crosslink between 2 water rudders, but if you DO use one it should be almost impossible for it to drag on the water surface at liftoff. If the tail of the float even TOUCHES at rotation, something is rigged wrong. If you are forcing the tails of the floats into the water deeply enough to drag the cross link, you're dragging the water rudders and probably making enough drag you'll never get airborne anyway.

I watched a guy once with a Senior Telemaster whose floats were set up with the nose of the floats WAAAY High. (or the nose of the airplane way low) He even had a spacer between the rear strut and the top lug of the float. He wanted the floats "to have enough angle to plane on top of the water"..... He motorboated all over the lake at full throttle,making impressive roostertails and holding full UP, and if he hit a wake or a wave he could juuuust get it to lift off, whereupon it leapt into the air like a rocketship. It couldn't rotate enough for the wing to make lift before the tail of the float hit the water surface.

I have a Senior Telemaster that takes off gently in 200 feet at 1/3 throttle, or at full throttle it 's airborne in 8 feet, but it's rigged properly. The wing is about 5 degrees positive to the top of the float. ANd it only has ONE (ernst)water rudder. With no rubber band. So it flips up as soon as the plane starts to move above idle speed. Nothing is dragging in the water and the tail of the float does not touch at rotation